Wavefield properties of a shallow long-period event and tremor at Kilauea Volcano, Hawaii

The wavefields of tremor and a long-period (LP) event associated with the ongoing eruptive activity at Kilauea Volcano, Hawaii, are investigated using a combination of dense small-aperture (300 m) and sparse large-aperture (5 km) arrays deployed in the vicinity of the summit caldera. Measurements of azimuth and slowness for tremor recorded on the small-aperture array indicate a bimodal nature of the observed wavefield. At frequencies below 2 Hz, the wavefield is dominated by body waves impinging the array with steep incidence. These arrivals are attributed to the oceanic microseismic noise. In the 2-6 Hz band, the wavefield is dominated by waves propagating from sources located at shallow depths (